Specifically the tail box flange bearings. Due to normal machining tolerances, the tail box flange bearings are either a press fit which will required an arbor press to install or they are an interference fit which you can just press in with your thumb. If the flange bearings require an arbor press to install you do not need to glue the bearings into place. If the flange bearings are easily installed/removed you will need to use thin CA to create a press fit. In order to do this, simply apply thin CA to carbon hole and let it wick into the layers of carbon. After the CA is dry, test fit the bearings into the tail box plate and vertical fin to see if you have a proper press fit.